{"title":"Use of Feedback to Compensate for Vacuum-Tube Input-Capacitance Variations with Grid Bias","authors":"R. L. Freeman","doi":"10.1109/JRPROC.1938.228781","DOIUrl":null,"url":null,"abstract":"The input capacitance of amplifier tubes decreases with increasing grid bias, thereby detuning the input circuits of intermediate-frequency stages in a superheterodyne receiver. The phenomenon is caused by a shift in space charge and also by feedback through the grid-plate capacitance. The change in input capacitance is of the order of 1.5 micromicrofarads for each of the two causes. A simple form of feed-back coupling compensates for this change of capacitance. The grid-cathode capacitance and an unbypassed resistor in the cathode lead provide the feed-back coupling.","PeriodicalId":54574,"journal":{"name":"Proceedings of the Institute of Radio Engineers","volume":"26 1","pages":"1360-1366"},"PeriodicalIF":0.0000,"publicationDate":"1938-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1109/JRPROC.1938.228781","citationCount":"2","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Proceedings of the Institute of Radio Engineers","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1109/JRPROC.1938.228781","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 2
Abstract
The input capacitance of amplifier tubes decreases with increasing grid bias, thereby detuning the input circuits of intermediate-frequency stages in a superheterodyne receiver. The phenomenon is caused by a shift in space charge and also by feedback through the grid-plate capacitance. The change in input capacitance is of the order of 1.5 micromicrofarads for each of the two causes. A simple form of feed-back coupling compensates for this change of capacitance. The grid-cathode capacitance and an unbypassed resistor in the cathode lead provide the feed-back coupling.
京公网安备 11010802042870号
京ICP备2023020795号-1
分享
求助内容：
应助结果提醒方式：
扫码关注我们
